I know what you're thinking, but no--this isn't an artificial heart with an iPod inside. The Swedish-engineered Tonium Pacemaker is actually an MP3 player designed around the needs of DJs (and DJ wannabes, like me), offering four channels of audio, a touch-strip crossfader, and a mind-boggling selection of EQ, pitch, loop, and audio effect features.
We first beheld this pitch-black disco DAP back in 2008, when it won us over with its gorgeous design, but broke our penny-pinching hearts with an $800 price tag. Since then, the Swedes at Tonium have retooled the Pacemaker with a ton of extra features, and now offer a second-generation model for the relatively affordable price of $499 (available though Amazon).
The second-generation Pacemaker shares the exact same hardware design as the original model (same outstanding packaging, as well), but the internal hard drive has shrunk from 120GB to 60GB. That's still enough storage for a pretty deep music collection, and a reasonable sacrifice for the $300 in savings over the original model.
Aside from a lower price and smaller hard drive, the second generation of the Tonium Pacemaker offers tons of little improvements to the firmware. One of my favorite new features automatically matches the tempo of one track to another, taking the guesswork (and skill) out of transitioning between songs. Tonium also threw in four new effects (Crush, Delay, Trans, and Wah), a vinyl emulation mode, independent EQ settings for the headphone and line out mix, new VU meters, a beat sync grid, and audio time-stretching for matching song tempos without shifting pitch.